Nov. 13, 2006
 
HEALTH: 24/7 Living Widens Waistline, Shortens Lifespan
 
By Lee Bowman
Scripps Howard News Service
 
In a 24/7 world where most everyone is wired and online, millions more Americans may be putting in overtime and night shifts, even if they're not in jobs that traditionally have overnight work schedules.
 
And that trend, a host of recent studies suggest, may put them at risk of both widening their waists and shortening their lives.
 
For instance, one mouse study in the journal Current Biology found that aged mice whose night and day were manipulated to simulate jet lag or rotating shift work died months sooner than those keeping a regular daylight cycle.
 
"As people get older, their ability to cope with shift work is impaired," said Gene Block, a professor of biology at the University of Virginia and coauthor of the study. "We know enough about the effects in elderly animals that one should be mindful of keeping an environment that promotes regular sleep cycles."
 
Human's natural body clocks, like those of all animals, regulate basic functions of sleep, hormone levels and internal temperatures that are crucial to metabolism and affect how cells age.
 
But as anyone who's been at a sleepover or pulled an all-nighter studying knows, staying up late encourages the munchies, as does not getting adequate sleep even with a fairly normal schedule.
 
"Some night shift workers eat at work in order to maintain their stamina, then go home and eat with their families. People can lose sight of portion control," said Netty Levine, a registered dietician and diabetes educator at Cedars Sinai Medical Center in Los Angeles.
 
But this isn't just a problem for adults. One recent study found that elementary school-aged children who slept less than 10 hours a night were three-and-a-half times more likely to be obese than peers who got 12 or more hours rest each evening.
 
Research at the University of Chicago suggests that sleep deprivation both decreases production of one hormone that makes us feel full and increases production of another brain chemical that signals hunger. Another study there found that curtailing sleep of young, healthy adults to four hours a night brought blood sugar and insulin levels into the diabetic range in a matter of a couple of days.
 
There's also evidence that having a late-night surge of stress hormones can carry over into the next day, leaving some people feeling particularly fatigued, while others sustain a boost of energy before they crash late in the day. So, of course, the late night memo or the wee hours awakening for an international conference call jolts the body's routine.
 
But experts say there are many things regular or occasional "shift workers" can do to reduce the negative health impacts.
 
One component is to have a wind-down, relaxation routine that might include a bath, meditating or reading, and should also include a light meal or snack if you haven't eaten recently. Being either too full or too hungry hurts the quality of sleep.
 
Avoiding caffeine for at least the last five or six hours before trying to sleep is important, too. "People working the night shift may consume large amounts of caffeine-laden beverages to stay awake, then if they are parents, may be forced to stay awake during the day in order to drive their children to and from school and other activities," Levine said.
 
And while exercise is important to a healthy lifestyle and to getting good sleep, it needs to be treated almost like caffeine -- too much exertion within a few hours of bedtime can leave you feeling pumped rather than tired.
 
"We encourage employees to take part of their one-hour break during their shift to walk around the hospital," said Emily Mitchell, another nutrition counselor at Cedars Sinai. "Short bouts of exercise can help you feel more alert and energized in the last part of your shift."
 
On the Net: www.sleepfoundation.org
 
Contact Lee Bowman at BowmanL@SHNS.com. Distributed by Scripps Howard News Service, http://www.shns.com